The present invention relates, generally, to temperature sensing and indicating devices and, more specifically, to a temperature sensing and indicating device which is inserted into a particular medium in order to sense and indicate the temperature of the particular medium.
The accurate and instantaneous sensing and indicating of a medium's temperature is critically important in many industries. These industries may be industrial and chemical processes and food preparation, to name just a few. The most accurate and expedient manner in which to measure the temperature of a medium is by inserting a temperature sensing device into the medium. The basic thermometer is such a device.
The processes involved with the above-mentioned industries require very accurate and very immediate temperature sensing and indicating. The basic thermometer with its mercury bulb and tube does not provide such accuracy and immediacy. Because of this other means of sensing temperature have been developed, such as thermocouples, thermistors and diodes. These devices typically convert temperature sensed into a signal which is then sent to an instrument which converts the signal into a readable temperature display.
Although those devices are well-known in the art, they do not, by themselves provide for the accuracy and ease of use necessary for many applications. Internal variables, such as calibration requirements, or external variables, such as shock from impact, must not compromise the integrity of the accuracy of a temperature sensing and indicating device when it is being inserted into a medium. The temperature so sensed must be easily and quickly, virtually instantaneously, readable or, in some manner, indicated to the user. This is especially true in food preparation.
Traditionally, in the preparation of food substances, especially meat, such as beef, individual taste preferences dictate the cooking status. Some meat, like pork, requires cooking to a certain temperature for health and safety reasons. Recently, a deadly outbreak of E-colibacteria in hamburgers has accentuated the safety aspects involved with cooking beef, especially ground beef. The ability to check temperatures of "doneness" and critical temperatures in bacteria-control areas, such as bone joints, will help to insure proper food preparation. This will, also, help to preclude the seriously detrimental and disastrous outbreaks of the bacteria related illnesses and, correspondingly, limit the liability exposure of restaurants or private food preparers.
A device for use in food preparation is taught by U.S. Pat. No. 3,504,544 to J. Tymkewicz, a co-inventor of the present invention. The device taught in the '544 patent was an insertion type temperature sensing and indicating device. It employed a movable probe with a similarly moveable temperature sensor therewithin. This device is limited in that the movable probe resulted in stress on the wire connections of the temperature sensor, and was sensitive to physical shock if dropped or severely impacted. Also, it did not provide a means for retaining the visual indication when the device was withdrawn from the medium. Accordingly, for the user to be able to see the temperature the temperature sensor had to be kept in the medium requiring the user to be in very close proximity to the medium being sensed.
A need exists, therefore, for an insertion temperature sensing and indicating device which has a temperature sensor which safely senses the temperature of a medium, can withstand a physical shock from dropping or a severe impact and has the ability to hold the visual indication when the temperature sensor is removed from the medium.